Chair base



of the inner end of Patented June 11, 1929.

UNITED STATES PATENT OFFICE.

SPENCER M. BUMP, 01 LAKEWOOD, OHIO, ASSIGNOB TO THE BETTCHER STAMPING & MANUFACTURING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

CHAIR BASE.

Application filed January 31, 1927. Serial No. 164,764.

This invention relates to chair bases or hubs such as are used especially in revolving chairs of the type having a central spindle in a pedestal having radiating legs.

An object of the invention is to provide a hub or base having a very simple assembly and in which, when assembled, the parts are in their set and final position. The invention provides improved means for clamping or fastening the inner ends of the legs to the hub in a fixed and rigid manner, the clamping being mainly efi'ected by the use of sheetmetal stampings capable of cheap production and quick assembly. Furthermore, the invention provides means whereby the clamping action may be completed by the use of a single nut screwed on the lower end of the central tube or barrel and acting to wedge the parts together, with dove-tailed joints between the legs and the hub structure, the clamping pressure of the nut being applied to the'under sides of the ends of the legs inthe hub in such manner that the dove-tailed tenons on the ends of the legs are forced upwardly between the converging clamping plates on opposite sides thereof, the said ten- 011s also converging upwardly so that they are wedged between the clamping plates. These plates are retained in place by transverse spacing plates which are slipped onto the central tube and are engaged by stopshoulders on said tube, said plates being held in position by the wedging action and the upward pressure of the nut.

Further advantages will be ap )arent from the following description and t e accompanying drawings, in which Fi 1 is a vertical sectional view of the hub; Fig. 2 a horizontal sectional view on the line 2-2 of Fig. 1; Fig. 3 a cross sectional view on the line 33 of Figs. 1 and 2; Fig. 4 a top plan one of the legs; and Fig. 5 a plan view of one of the spacing plates.

Referring particularly to the drawings, 6 indicates the radiating legs of a chair pedestal or base, each leg having a dove-tailed tenon 7 at its inner end, the side walls 8 of which tenons converge upwardly. The central tube or barrel of the hub is indicated at 9, having the bore for the spindle of thechair (not shown). This tube 9 has an upper shoulder 10 and a lower shoulder 11 extending around the same, the tube beingreduced "exteriorly to form saidshoulders, and the tions 17 on the plates forming distance pieces or spacers between the adjacent legs.

A pair of clamping plates 18 are associated with each tenon, to form clamps therefor, these plates fitting between the inclined side walls of the tenons 7 and the adjacent edges of the cooperating notches 16.

As shown in Fig. 3, lugs on the upper ends of the plates 18 may be fitted in slots in the top plate 19, where they may be upset or riveted, as indicated at 20, said top plate 19 being an annular plate which extends loosely around the top of the hub 9 and overlies the inner ends of the legs 6, to which the plate is fastened by screws 21.

A bottom plate 22 fits loosely over the lower end of the tube 9 and is secured to the under sides of the legs 6 by the screws 23, the plate 22 being also confined by the nut 13.

In assembling the parts, the tenons 7 of the legs, with their side plates 18, are entered in the notches 16 in the spacing plates 14 and are inserted between the top and bottom plates 19 and 22, and the tube 9 is then applied to the foregoing assembly, with the spacing plates seated against the shoulders 10 and 11. The nut 13 is then applied. As stated, the tenons 7 are wedge-shaped in vertical cross section, the side walls thereof converging from the bottom toward the top. -When the nut 13 is tightened against the bottom plate 22, the tenons of the legs are forced upwardly and the plates 14 are pulled downwardly, forcing the side plates 18 into wedging engagement with the sides of the tenons 7, which latter are thereby clamped into rigid engagement with the metal parts of the hub in the final or set position. plates 18 prevent the edges of the notches-or recesses 16 from cutting into the wood of the tenons 7. In the event of any looseness, incident to wear or shrinkage, the looseness may .be taken up by 'screwix'ig -up'tlfennt 13. An

The clamping tenons 7 through the action of the nut 13, is to shaped tenons at their plates fitting flatly against opposite sides of ing plates to increase the wedging action of the plates 18 against the sides of the tenons, thereby tending to bind these clamping plates more tightly against the sides of the tenons. The assembly thus tends automatically to take up any looseness or wear between the parts.

The parts may be cheaply constructed, largely from metal stampings, and quickly and easily assembled, and with very little riveting or screw-threading, forming in effect a self-locking construction for rigidly connecting radial legs to the pedestal or barrel of a chair or the like. It will be noticed that the legs are assembled or fastened together as'a unit, distinct from the barrel, and are then clamped to the barrel by movement of the unit as a whole lengthwise of the barrel, the clamping being effected or completed by the wedging action of the plates 18 against the sides of the tenons.

Having thus described my invention, what I claim is 1. A chair base comprising a central barrel, legs having upwardly converging oppo site side walls at their inner ends, clamping plates adapted to engage said walls, and spacing plates supporting said barrel and located between said barrel and the inner ends of the legs and having projections engaging the outer sides of said clamping plates to force. the same into gripping contact with said walls.

2. A chair base comprising a central bar-- rel having stops thereon, legs having wedgeshaped tenons at their inner ends, and spacing plates seated against said stops and located between the barrel and the inner ends of the, legs and having projections adapted to exert pressure against opposite sides of said tenons to clamp the same by the wet g- .ing action due to the movement of said plates longitudinally of said tenons.

3. A chair base comprising a central barrel having shoulders thereon, legs having wedge inner ends, clamping said tenons, horizontally arranged spacing plates fitting around the barrel and resting against said shoulders and having projecthe outer sides of said clampforce the same against the, tenons through the movement of the spacing plates longitudinally of said tenons.

4i. A chair base comprising a central bartions engaging rel having shoulders thereon, legs each having side walls at its inner end converging upwardly, spacing plates located between the barrel and the inner ends of the legs and seated against said shoulders and having projections adapted to exert pressure against opposite sides of the tenons to clamp the latter by the wedging action due to the downward movement of said plates with respectto said tenons.

v 5. Means for clamping radiating legs to a central barrel, said means comprising wedge shaped tenons on the inner ends of the legs, a barrel, top and bottom plates attachedto the legs and loose with respect to the barrel, and spacing plates located between the barrel and the inner ends of said legs and between the top and bottom plat-es, said spacing plates being carried by the barrel and having projections between which the opposite inclined sides of the tenons are slidably engaged to clamp the same by movement lengthwise of theibarrel.

6. The means set forth in claim 5, and a nut on the lower end of the barrel, bearing against said bottom plate. a

7. A chair base comprising a central barrel, radiating legs having wedge-shaped tenons at their inner ends, top and bottom plates loose on the barrel and fixed to the legs, and means carried by the barrel and engageable by shifting the tenons lengthwise of the barrel to clamp said tenons and legs to the barrel.

8. A chair base comprising a central barrel having a shoulder thereon and a threaded lower end, radiating legs having wedge- ,shaped tenons at their inner ends, a bottom plate loose on the barrel and fixed to said legs, aspacing plate between the. tenons and the barrel and resting against said shoulder, clamping plates at opposite sides of said tenons, said spacing plate having projections engaging the outer sides of said clampingplates, and a nut on the threaded end of the barrel bearing against said bottom plate, to wedge the tenons upwardly between said clamping plates.

9. A chair base comprising a central barrel having shoulders thereon, spacing plates horizontally disposed around thebarrel and seating against said shoulders, radiating legs having opposite converging surfaces at their inner ends, said spacing plates having recesses into which said legs extend, and clamping plates between said surfaces and the edges of said recesses.

10. A chair base comprising a central barrel having shoulders around'the same and a threaded lower end,radiating legs having upwardly tapered dovetailed tenons at the inner ends thereof, top and bottom plates extending loosely around the barrel and fixed to the legs, clamping plates extending along the opposite sides of the tenons, spacing plates seated against said shoulders and having recesses into which said tenons and clamping plates fit, and a nut on the lower end of the barrel bearing against said bottom plate.

11. A chair base comprising a central barrel having longitudinally spaced stops thereon, legs having opposite converging surfaces at their inner ends, spacing plates arranged horizontally about the barrel and adapted to be engaged by the stops thereon and having recesses into which the inner ends of said legs extend, a plate for the said legs and through which the barrel extends, and clamping plates suspended from the last-mentioned plate and located between the surfaces at the inner ends of the legs and the recesses therefor.

12. A chair base comprising a central barrel having longitudinally spaced stops thereon, legs having opposite upwardly converging surfaces at their inner ends, spacing plates arranged horizontally about the barrel and adapted to be engaged by the stops thereon and having recesses into which the inner ends of said legs extend, an upper plate for the said legs and through which the barrel extends, clamping plates suspended from said upper plate and located between the surfaces at the inner ends of the legs and the recesses therefor, a bottom plate secured to the lower ends of the legs and through which the said barrel extends, and a nut threaded on the lower end of the said barrel and adapted to engage the bottom plate.

13. A chair base comprising a central barrel having longitudinally spaced stops thereon, legs having opposite upwardly converging surfaces at their inner ends, spacing plates arranged horizontally about the bar rel and adapted to be engaged by the stops,

thereon and having recesses into which the inner ends of said legs extend, an upper plate for the said legs and through which the barrel extends, and clamping plates suspended from said upper plate. and located between the surfaces at the inner ends of the legs and the recesses therefor.

14. A chair base comprising radiating legs each having at opposite sides of its inner end surfaces which converge in a vertical direction, one or more transverse spacing plates having recesses adapted to receive the opposite converging surfaces of said legs, and clamping plates interposed between the said surfaces and the edges of said recesses.

15. A chair base comprising radiating legs each having at opposite sides of its inner end surfaces which converge in a vertical direction, one or more transverse spacing plates having recesses adapted to receive the opposit-e converging surfaces of said legs, clamping plates interposed between the said surfaces and the edges of said recesses, and apertured plates secured to the top surfaces and the bottom surfaces of the inner ends of the legs.

16. A chair base comprising radiating legs each having at opposite sides of its inner end surfaces which converge in a vertical direction; one or more transverse spacing plates having recesses adapted to receive the opposite converging surfaces of said legs, and clamping plates interposed between the said surfaces and the edges of said recesses, the said spacing plate or plates being longitudinally adjustable with reference to the clamping plates thereby to wedge the latter against the said converging surfaces.

17. A chair base comprising a plurality of radiating legs each having at opposite sides of its inner end surfaces which converge in a vertical direction, and a hub assembly for such leg ends, the said assembly comprising an upper plate and a lower plate secured to the inner ends of the said legs, a central barrel between the upper and lower plates, clamping plates for the converging surfaces, and one or more spacing plates surrounding the said barrel and. having recesses for the clamping plates.

18. A chair base comprising radiating legs each having at opposite sides of its inner end surfaces which converge in a vertical direction, one or more transverse spacing plates having recesses adapted to receive the inner ends of the legs, an upper plate and a lower plate secured to the inner ends of said legs, and a pair of clamping plates for the converging surfaces at the inner end of each leg and each pair adapted to be received within a recess of said spacing plate or plates, the said clamping plates being movably connected to one of the second mentioned plates.

19. A chair base comprising a central barrel, a plurality of radial legs having wedging projections on the portions of the legs presented toward said barrel, means for fastening the said legs together whereby they may be moved as a unit lengthwise of said barrel, means for so moving the legs lengthwise of said barrel, and means cooperating with said wedging projections and actuated by such movement of the legs to clamp the legs to the barrel.

20. A chair base as specified in claim 19, and a nut on the lower end of the barrel engaging the lower end of such unit thereby to effect the movement of the unit lengthwise of said barrel.

In testimony whereof, I hereunto afiix my signature.

SPENCER M. BUMP. 

